With the widespread popularity of microwave cooking techniques, considerable attention has been given in recent years to the packaging of food items for preparation in microwave ovens. One area which has received significant efforts is the packaging of popcorn for cooking by microwave.
Perhaps the most widely adopted commercial packaging technique employs a flexible sack folded and sealed within an outer film wrap which must be discarded. The sack has raw corn and oil disposed against the sack's side wall which often incorporates a microwave susceptor material to speed heating. Upon cooking, the exploding kernels of corn expand and fill the sack. The efficiency of cooking in such an arrangement is less than optimal, and often results in uncooked kernels and burned kernels. The finished cooked popcorn container is not as convenient for handling as the more traditional semi-rigid cardboard containers in which cooked popcorn is usually vended.
Others have proposed cardboard boxes which are shipped with separate sealed containers having premeasured corn and oil amounts which the user must empty into the box prior to cooking. Such a system is illustrated in U.S. Pat. Nos. 4,553,010 and 4,678,882.
Yet another approach to this problem is to provide the corn and oil in a bowl-type container sealed by an expandable film cover which unfolds or expands upon cooking. None of the approaches previously known, however, provides the simplicity, economy, cooking efficiency and finished product results which we have discovered by utilization of the present invention. The invention provides a package of individual popping corn which may be immediately placed in the microwave without further manipulative steps other than the simple step of closing fold-down top flaps. The packaging system of this invention generates no waste packaging material or other trash in readying the corn for cooking in the microwave or for eating after final preparation. The design of the package is an efficient one for the complete popping of corn to abundantly fill its container. The package is provided with means for comfortably removing the hot box from the oven and opening it for consumption. The end cooked product is contained in an easily handled, semi-rigid container which may be readily reclosed.